Combining cosmological SPH simulations with a previously developed Ly \alpha production/transmission model and the Early Reionization Model ( ERM , reionization ends at redshift z \sim 7 ) , we obtain Ly \alpha and UV Luminosity Functions ( LFs ) for Lyman Alpha Emitters ( LAEs ) at 5.7 \leq z \leq 7.6 .
Matching model results to observations at z \sim 5.7 requires escape fractions of Ly \alpha , f _ { \alpha } = 0.3 , and UV ( non-ionizing ) continuum photons , f _ { c } = 0.22 , corresponding to a color excess , E ( B - V ) = 0.15 .
We find that ( i ) f _ { c } increases towards higher redshifts , due the decreasing mean dust content of galaxies , ( ii ) the evolution of f _ { \alpha } / f _ { c } hints at the dust content of the ISM becoming progressively inhomogeneous/clumped with decreasing redshift .
Using the model assumptions , clustering of sources has little effect on the Ly \alpha LF for a cosmic hydrogen neutral fraction \chi _ { HI } \leq 10 ^ { -4 } , a value attained at z \leq 6.6 in the ERM .
However , during the initial reionization phases ( z \lower 2.15 pt \hbox { $ \buildrel > \over { \sim } $ } 7 ) the clustering photoionization boost becomes important .
We quantify the physical properties of observed LAEs and their redshift evolution , for which we give handy analytical fitting functions .
Halo ( stellar ) masses are in the range 10.0 < \log M _ { h } < 11.8 ( 8.1 < \log M _ { * } < 10.4 ) with M _ { h } \propto M _ { * } ^ { 0.64 } .
The star formation rates are \dot { M } _ { * } = 3 - 120 { M _ { \odot } yr ^ { -1 } } , mass-weighted mean ages are t _ { * } > 20 Myr at all redshifts , while the mean stellar metallicity increases from Z = 0.12 { Z _ { \odot } } at z \sim 7.6 to Z = 0.22 { Z _ { \odot } } at z \sim 5.7 ; both t _ { * } and Z positively correlate with stellar mass .
The brightest LAEs are all characterized by large \dot { M } _ { * } and intermediate ages ( \approx 200 Myr ) , while objects in the faint end of the Ly \alpha LF show large age and star formation rate spreads .
With no more free parameters , the Spectral Energy Distributions of three LAE at z \sim 5.7 observed by Lai et al .
( 2007 ) are well reproduced by an intermediate age ( 182 - 220 Myr ) stellar population and the above E ( B - V ) value .
The model uncertainties , mostly related to the simplified treatment of dust and to the possible effects related to gas outflow/infall , are discussed along with their impact on the results .